What is the problem? This:
- BMW M5 (2005-2010), BMW M3 (2008-2013) can suffer early bearing failure due to inadequate rod bearing clearance.
- Insufficient clearance means insufficient oil flow, excessive bearing surface heat, and premature wear.
- These symptoms can lead to early bearing failure and a very expensive engine rebuild.
- Problem can be addressed during engine rebuild, but it's expensive.
- Some people switched to thinner oils -- as a stopgap measure.
- Other stopgap measures include anti-friction teflon coated factory bearings, WPC anti-friction treated factory bearings, and custom bearings with same clearance as stock.
- "Coated" factory bearings decreased clearance. This is not a good idea.
- WPC treated bearings slightly increase clearance, but are a stopgap.
- Custom bearings keeping factory clearance doesn't fix the problem, but allows you to track lead and copper in Blackstone oil analysis.
- Newer factory bearings (2010.5 and later) are made from tin-aluminum, not lead-copper. Tin-aluminum bearings are 4-times harder on the surface than lead-copper bearings. This extra hardness shows signs of doing more damage to motors as there seems to be more bearing failures with 2010.5 and later vehicles. Tin-aluminum bearings also don't show the same signs of premature wear in Blackstone oil analysis due to lack of lead and copper.
- A better solution was needed.
If you have insufficient oil flow and premature wear you will eventually lose the motor. When it will happen depends on use but it will happen. So what is the solution? New bearings that are made to the proper clearance of course and for those who truly want peace of mind when tracking a dry sump oil system is recommended. BMW skimped in this area which is no surprise.
So how do you replace the bearings? Well, this DIY from SYT_Shadow covers it. For those not comfortable doing this yourselves, shops such as GermanAutoWerks or @alex@ABRhouston can do it for you.
Special tools used
3/8Ē 12 point socket to install the BE-ARP bolts
6 inch T30. I had a 4 inch one and it doesnít work, so I lost an hour driving around looking for one. Do not start the work without one!
Special hardware used
BW street/track (Group N) engine mounts. If yours is a street car, I suggest replacing them with OEM items
BE Bearings. I donít understand why anyone would use something else
BE-ARP bolts. Again, these should be the default choice for everyone. Besides being the best bolts for these engines, you do not want to be angle torqueing stuff in this tight a space. Somewhere, someone is thinking Ď$500 is a lot for boltsí. Well good luck with that...
Plastigauge. You need the green one. You can buy some at http://www.summitracing.com/search/p...-77-plastigage
Two different Computorq3 electronic torque wrenches. I have the ĹĒ one as well as the ľĒ, which covers the range of required torque. To do this with a crappy/inaccurate torque wrench is a waste of time.
Harbor Freight Engine hoist. I used this on my E46M3 rod bearing DIY. Itís a cheap piece of hardware that works exactly as designed!
Snap-on 3/8 electric ratchet. This makes everything a lot easier. There are a TON of bolts you have to remove to do this job, I highly suggest either this or the Milwaukee one
This took 12h, first time doing it. We usually are slow workers. It was 10h one day and 2h the next. There is no doubt that if we were not doing a DIY - which requires you to spend lots of time pausing to take pictures, etc and renders one of the two people working useless - it would have taken significantly less. There was also one snag with the 4Ē T30 and subsequent easter egg hunt which took time, but you get the idea.
Torque specs (courtesy of E92love)
oil pan bolts (30 qt) and all other M6 bolts inside/outside engine: 10 Nm
steering rack bolt on step 6 (1 qt) (M8): 21 Nm
E12 transmission to oil pan bolts (4 qt) (M10): 38 Nm
engine mount nuts. 1 top, 1 bottom on each side: 56 Nm
the 6 front subframe bolts (M12): 108 Nm
rear 2 most subframe bolts (M10): 56 Nm + 90 degree
re-enforcement plate bolts (7 qt) (M10): 56 Nm + 90 degree
4 water pump pulley bolts (M6): 10 Nm
pulley tensioning system on both sides. 2 for each side (M8): 19 Nm
Part numbers (courtesy of ///Mobbin)
11137841085 - e92 m3 oil pan gasket
Oil pickup tube/system parts that I also ordered (just in case):
11417839832 - pickup tube o-ring
11417839833 - pickup tube o-ring
11417838534 - suction pipe gasket
11427837997 - oil filter kit (oil filter, o-rings, crush washers)
07119904550 x 2 - oil pan drain plug (includes crush washer also)
07-12-9-905-537 - 16 x oil pan screws
07-12-9-905-599 - 12 x oil pan screws
07-12-9-905-600 - 2 x oil pan screws
12611744292 - oil level sensor o-ring
11812283798 - engine mounts (might include nuts, not sure)
07119904025 x 4 - engine mount nuts
As you will drain the oil you will need to refill it. A typical oil change in this car is 8 quarts/liters and a little more. While changing rod bearings you remove a massive amount of oil which would typically never leave the engine, which means you will need 9.5 bottles to fill it back up so the car is happy. Protip: have more than that just in case!
At times the DIY pics will show something I havenít explained yet, so it may seem out of order. That is because at times you try different things. You should follow the order of instructions explained here
Rod bearings do not require break in. If you used assembly lube, you should change the oil after a few thousand miles. Both BE Bearings and Bimmerworld were contacted to weigh in on this. When you think of it, a rod bearing should never have contact with the crank. Regular break in is more about seating the rings and walls than anything else
I am told this can be done without removing the fan. Next time I do the job I'll take pics and update the thread accordingly. Doing this without removing the fan will cut out several step and save quite a bit of time, I definitely suggest you try that first
Putting the DCT into neutral. The 6MT guys can skip this part
Lift the shift boot from the front by pressing rearwards and unclipping it
There is a black guard which you can see in this pic. With a screwdriver, move to forward and it will slide out of the way
Here you can see the white lever that hides behind the black guard. You put a screwdriver in there and move it. The car will go into neutral and complain about it
Starting from the top, we remove part of the air intake ducting. There are two push pins that go down into the black brace-like bar and two screws which go into the car
When all four are removed you can pull the front part of the duct towards you
This releases the rear part of the duct
Install your engine support brace. Here are some pics of mine. You need to slightly tension it Ďupwardsí so that it is trying to pull the engine up, just a little bit. Remember the engine mounts are still installed so the engine cannot move much
I try to minimize potential energy, so I put a cushioned mat on top of the sharp parts of the engine support bar and then rest the hood on it
Remove the front wheels
We remove all the black felt underbody panels. There are many, many little screws
Note the three rear ones of the front felt part are different than the rest
When you remove the side front Ďwingsí you can see the cable structure that supports the front felt part. You slide the top sideways and then out so it falls freely. Note you don't need to remove the two screws that hold the bottom of those cables.
Continue removing the bottom felt pieces
More felt pieces
This is what youíre left with. Note the clips on the bottom of the fan which hold piping. Remove all the pipes from the clips
Remove the aluminum chassis brace. There are 7 bolts, one of them is conveniently hidden inside the front center jack support
Remove the tranny felt underbody
A leaky DCT panÖ wonderfulÖ Iíll get to that sucker later
Go back to the top of the car
We now move onto the fan. I did the removal and reinstallation without removing any more of the air intake. Itís easier if you remove the air box, but it can be done like this
The radiator is held on by a single torx bolt on the passenger side. You can see it here. Remove it
Unclip the large connector right by the torx bolt
You can try sliding the fan upwards but it faces resistance. This is because thereís a clip that has to be undone on the driver side and the bottom of the fan has pipes clipped onto it
Lets go for the clip on the driver side, on the edge of the fan. You can just about put your arm in there and unclip it while you move the fan up. Itís a really tight, PITA fit but eventually you will release the whole fan after a lot of wiggling.
Go back to the bottom of the car
Right by all the pipes you disconnected from the fan you have another ĎUí pipe which is bolted onto the subframe. It has 3 bolts and one nut. One of the 3 bolts is shorter, that one goes on the passenger side of the rack
In the wheel well, remove the ABS/Brake lines from where theyíre connected to the strut
Drain the oil. Remember there are two drain holes in the S65
Remove the front sway bar links. I see BMW learned from the bad design of the E46M and now you can use two regular open ended wrenches
The next thing in the way of lowering the subframe is the belt tensioner. It is half attached to the engine and the oil pan, so we need to loosen it.
As itís the tensioner itís very hard to move and we must remove the belt first
Start by taking off the cap to access the bolt underneath. This is what weíll use to release tension and remove the belt
You then use a wrench to release the tension on the belt and slide the belt off. Once the belt is off, release the tension slowly until the tensioner reaches the end of its travel
Here you see the base of the tensioner which is still out of our reach because the subframe prevents us from reaching the bolts. Once we lower the subframe a bit weíll return
Prepare to start undoing lowering the subframe.
First we unclip different wires. Here you can see two different cables that must be disconnected. One is to the lower left and goes to the arm which controls the xenon position, the other is a white connector
Remove the ground from the engine block
There is a bracket on the front driverís side of the car. Itís held on with two bolts. Remove them
Notice the wrench Iím holding
Rotate the steering rack towards the passenger. Do it slowly and youíll be able to peek at the steering rack bolt that has to be removed. You see this looking from the driverís side of the wheel well
You need a E10 for the steering rack. Before touching this, draw a couple of lines between both parts you will uncouple. This allows you to mate it up exactly as it was. This is not poke-yoke, so itís possible to set it back up with a crooked steering wheel. If that were to happen to me, Iíd just get the car aligned, it is not the end of the world. I drew two lines and was able to reattach it perfectly
Here you can see the two lines
You need an extension to get there
Now we are ready to loosen then lower the subframe. Lets get the 6 bolts first. Note at this point I unscrew the 6 bolts but without removing them. You could also just remove them, the subframe weighs nothing and will happily hang from the suspension
After making sure no cable is about to snap, I release the bolts completely
We can revisit the tensioner now that the subframe is a bit lower. Remove the three bolts
Go to the back of the oil pan where thereís a surprising amount of cables. Unclip them and release the harnesses
Itís time for the oil pan bolts! Please take note of how long the T30 needed is. I used a 6 inch one because the 4 inch 'extra long' one I had bought for this job was insufficient
Remove all the oil pan bolts. There are many of them. The ones you need the extra long T30 are in the back of the oil pan
I followed smart peopleís advice and inserted the oil pan bolts into the cardboard part that comes with the new oil pan gasket. There are a few diagrams I made. Left is the front of the engine, right is the rear. I put the car behind some pictures to make it extra clear. Note the two different lengths of bolts that are used, so take note!
Just like in the E46M, the back of the oil pan/tranny interface has 4 long bolts that go into the oil pan. I used an open ended wrench on 3 of them as a regular socket doesnít fit
After that, the oil pan just falls down a bit. An oil pipe and the subframe avoids it from going far
Here you can see the fat pipe in the front which is avoiding our progress
Time to remove that pipe. Itís held on with two screws and has a mini gasket. Remove the short fat pipe. Note that this pipe has threadlocker on it, so be sure to reapply blue threadlocker when reassembling
Now you can drop the oil pan further
Next up are the two remaining oil pipes plus the supports. Remove them all. Note that all this hardware has threadlocker on it, so be sure to reapply blue threadlocker when reassembling
Finally, we can start accessing the rod bearings!
Cylinder 1 (most to the front of the car) is in the perfect position. You can do rods 1 and 2 without rotating the engine.
I went cylinder by cylinder completing the work
After loosening the two bolts that hold a cap, sometimes you need to give it a little nudge with a rubber mallet
Note these are cracked forged rods which, besides being awesome, are cylinder and side specific. That means cylinder oneís cap only mates to cylinder one and the left side must go with the left side. I guess enough people screwed this up with the E46M3 that they started numbering the sides, so now one side of each rod and cap has numbers are the other doesnít.
Once you have a cap in your hand, you remove the old bearing. Easiest way I've found to do that is rotating it from the belly sideways, if need be one way and the other, and it'll slide right out.
Next get a new bearing, insert it into the cap (it is a bit springy, but it does fit), note that top and bottom bearings are identical in my case. Some BE Bearing sets will be marked 'top' and 'bottom' shells, so if that is the case be sure to put the 'top' shell into the rod, the bottom into the cap. The ones I received were undesignated tops and bottoms and could be installed interchangeably
Then, get some clean oil or assembly lube and cover the surface of the bearing. I misplaced my assembly lube but apparently oil works just fine according to technical folks, so I used that. I used a clean glove to spread the oil on, replacing it every time it got dirty because I touched another surface
First insert the bearing on the cap (where you can see what you're doing, and practice doing it by feel only), then the rod. To access the upper bearing just push the piston up by the rod and then nudge the old bearing sideways to get it out, just like you did on the cap.
Cap 1 removed!
Journal looks happy
Here are my new goodies
This is a pic of the socket you need for the ARP bolts
These are torqued to 50ft-lb. Note this entire DIY is in Nm except the rod bolts, which are made by ARP so they use an imperial fastener and imperial torque specs. First I torqued both sides to 30ft-lb, then to 50. I wanted to ensure they were well settled
BE-ARP bolts come with lube. Thereís like 20x the amount needed even though at the beginning I thought there was too little. You are supposed to cover the threads and head with lube as seen below
I wanted to write this up because Iíve always been curious. As luck would have it, the massive box of plastigauge I had bought sometime in the past had every size known to man except the one I wanted. Nonetheless, I went through the procedure even though the numbers here donít mean anything
You are supposed to use the new bearings here, but I used the old ones as the measurements in my case are worthless as I donít have the right material
Note that the desired range when using green plastigage I linked above which is in inches is:
You should see anything from 0.0022 - 0.0028. Even the upper end of 0.0030 isn't the end of the world. The connecting rod bores seem to wear bigger over time.
For those that are on the upper end of the clearance spectrum that you'd like to bring down, get some 600-grit wet sandpaper, and sand the parting lines (with the paper wet). Go 6-8 swipes in each direction with light-to-medium pressure (5lbs - 10lbs pressure). Clean the dust thorougly, re-install, and re-measure. If it's still not where you want it, do it one more time. I don't think I'd do it more than twice though.
First you lay a little piece of plastigauge across the belly of the rod bearing
Then, you torque it down to whatever the fastener you use takes. Again, I used the old fasteners and tightened to 30ft-lb because my sizes were wrong
Finally, you remove the cap again and then compare against the piece of paper that comes with the plastigauge
According to this, I have 0.0076mm of clearance
After the first two rods youíll have to move to the third and fourth. You need to rotate the engine. You do this with a 32mm socket at the front of the engine and turn clockwise
Eventually the third and fourth rods with be right in the middle and you can work on those. Repeat the process until youíre done
Lets see what the bearings look like!
I also removed the engine mounts and swapped them for BW units. Note that after only 36k miles mine were not looking too hot
When reinstalling, you bolt the engine mount to the subframe instead of to the engine cradle where it just was
Installation is the reverse of disassembly, but just in case I show the steering rack which is the hardest part. Start raising the subframe slowly and the parts will more or less mate up
Note you should reapply green loctite to the steering rack bolt before reassembling
Donít forget to fill up with oil and change the oil filter before turning the engine on!
As the engine is completely emptied of oil, someone suggested to pull fuse 39 so the engine doesnít start. You can see that below. I did this, but the engine still fires and then wonít start, which I donít think is an advantage. If it just cranked then yes, but by pulling this fuse it cranks, then fires, then dies. After a few tries I reinstalled the fuse and turned the engine on, leaving it alone for a while so it heated up. I recommend you do that from the beginning